Lupus mimickers

Referrals for rheumatologic evaluation following a positive antinuclear antibody test result. A cross-sectional single center Brazilian study

BACKGROUND

In general, patients are referred for rheumatological evaluation due to isolated laboratory abnormalities, especially antinuclear antibody (ANA) positivity, with the risk of more severe patients remaining on the waiting list for longer than desired. The aim of this study was to analyze the demographic, clinical, and laboratory information of patients referred to a specialized rheumatological care unit because of positive antinuclear antibody.

METHODS

This is a retrospective study of 99 out of 1670 patients seen by the same rheumatologist between 01/01/2011 and 01/01/2019. Patients whose referrals were exclusively due to the ANA test result and the specialist's final diagnosis being "abnormal finding of serum immunological test" (ICD-10 R769) were included. Sociodemographic, clinical, and laboratory information were extracted from the consulting rheumatologist's chart. Descriptive statistics were used for data analysis.

RESULTS

A total of 99 patients were included, most of whom were female (84.8%) with a median age of 49 years. At the moment of specialist's appointment, 97 patients (97.9%) repeated the ANA test, and 77 patients remained positive. Of these, only 35 (35.35%) were in a high titer range (greater than or equal to 1:320). Complete blood count for cytopenia's investigation was not performed in a high percentage of patients (22.2%), as well as urinalysis (31.3%). In addition, more than 70% of patients score 0 to 1 classification criteria for Systemic Lupus Erythematosus, according to SLE - ACR 1987 (American College of Rheumatology) and SLICC 2012 (Systemic Lupus International Collaborating Clinics).

CONCLUSIONS

Most patients are still referred for specialized evaluation due to the misinterpretation of laboratory tests that were inappropriately requested in patients without clinical evidence of autoimmune rheumatic disease.

A Challenging Diagnosis of Febrile Pancytopenia in a Patient With a History of Autoimmune Disease

Pancytopenia is a hematologic condition characterized by a decrease in all three peripheral blood cell lines. There are many causes of pancytopenia, and the proper approach is required for accurate diagnosis. Brucellosis and systemic lupus erythematosus (SLE) are both diseases that can initially present as pancytopenia, both of which require a targeted workup to diagnose. Due to the immune system's complexity, many distinct diseases may have similar symptomatology. Furthermore, infections and rheumatological diseases can stimulate the same molecular pathways and trigger T and B cells. This creates a cross-reactivity between microbial peptides and self-peptides, allowing the spread of microbial-specific T cells that can also respond to self-peptides. Brucellosis has broad clinical manifestations, often mimicking many other diseases, such as rheumatoid arthritis, sarcoidosis, and SLE. In addition, brucellosis-induced autoantibody production has been described as a triggering factor for immunologic reactions, elevating rheumatological markers by a poorly understood mechanism. Finally, SLE is a well-known medical condition that can mimic several medical conditions, including brucellosis.  We present a case of a young patient who was admitted with febrile pancytopenia. The patient also had IgM antibodies positive for brucellosis and high immune markers for SLE. She was treated for both diseases, and afterward, in retrospect, it was confirmed that the patient did not have acute brucellosis.

Tuberculosis mimicking the onset of systemic lupus erythematosus flare: Case based review

AIM

To analyze the clinical features of lupus-like tuberculosis (TB).

METHODS

Three cases of TB imitating systemic lupus erythematosus (SLE) flare were collected in our hospital. Based on literature review, there are only 3 reports of TB resembling lupus flare rather than SLE per se.

RESULTS

The 3 cases of lupus mimickers, with a mean age of 30.3 years, ranging from 27 to 32 years, had atypical features of SLE, namely no typical butterfly erythema, lupus hair, alopecia or proteinuria, similar to the patients reported in the 3 previously mentioned studies. Emergence of different autoantibodies like anti-nuclear antibodies, anti-double-stranded DNA, anti-nucleosome antibodies, and anti-histone antibodies could occur in TB, mostly as an epiphenomenon. In patients with specific serological anti-Sm and hypocomplementemia, active TB cannot be easily ruled out. The presence of autoantibodies neither altered the clinical manifestations and radiographic findings of active TB, nor were detectable after infections are resolved. The resistance of the SLE manifestations to the steroid and immunosuppressive treatment suggests the contribution of an infectious disease.

CONCLUSION

TB stimulated the production of autoantibodies, with shared affinity for mycobacteria and human antigens, which may have led to lupus mimickers.

TAFRO syndrome: A severe manifestation of Sjogren's syndrome? A systematic review

BACKGROUND

Sjögren's syndrome (SjS) is a systemic autoimmune disease characterized by lymphocytic infiltration of the salivary and lacrimal glands associated with sicca syndrome. TAFRO syndrome is a systemic inflammatory disease of unknown cause, characterized by Thrombocytopenia, Anasarca, Fever, Reticulin fibrosis, Renal dysfunction and Organomegaly, first reported in 2010 in Japanese patients. Despite their rarity, both conditions have been concurrently reported in several patients during the recent years, hence questioning the existence of shared or related features.

METHODS

A systematic review of the literature regarding SjS associated with TAFRO syndrome (SjS-TAFRO) was performed. The 2019 updated Masaki diagnostic criteria were used for TAFRO syndrome and SjS was considered when the diagnosis was mentioned by the authors, necessarily with either anti-Sjogren's Syndrome A (SSA) ± anti-Sjogren's Syndrome B (SSB) antibodies and/or histological evidence of focal lymphocytic sialadenitis.

RESULTS

Ten cases of SjS-TAFRO have been reported in the literature to date. Compared to SjS patients without TAFRO syndrome, these 10 SjS-TAFRO had a lower female predominance (2.3:1 vs 9:1 women to man ratio) and a higher frequency of anti-SSA antibodies (90% vs 70%). All fulfilled the three major Masaki criteria i.e., anasarca, thrombocytopenia, and systemic inflammation. Seven of them (70%) had megakaryocyte hyperplasia or reticulin fibrosis in the bone marrow. Lymph node biopsy was performed in 8 out of 10 cases (80%) and results were consistent with Castleman disease in 6 (75%). Eight of them had developed renal failure (80%) within six months. Nine of them (90%) had organomegaly, with hepatosplenomegaly in 8 cases and splenomegaly alone in 1.

CONCLUSION

This review brings new insights regarding TAFRO syndrome and suggests it could be a severe manifestation of SjS. The identification of shared abnormal signaling pathways could help in the therapeutic management of both diseases, which face an unmet therapeutic need.

COVID-19 in an Adult with Down Syndrome: Impact on Autoimmune Response

We here report a case of COVID-19 with effusion prior to the development of pneumonia in an adult with Down syndrome. Serositis due to rheumatic disease was initially suspected because of a high titer of serum autoantibodies and leukocytopenia; however, SARS-CoV-2 infection was confirmed by reverse transcription polymerase chain reaction on admission after previous negative tests. Several cases of COVID-19 have been associated with autoimmune responses along with some cases of COVID-19 with autoimmune manifestations. Furthermore, patients with Down syndrome have a higher mortality risk from COVID-19 than the general population, and it is believed that a high sensitivity to the interferon response may contribute to the increased severity of the disease. Thus, careful attention should be paid to autoimmune manifestations due to SARS-CoV-2 infection for ensuring a proper and timely diagnosis, especially in patients with Down syndrome.

Transient Systemic Lupus Erythematosus-like Syndrome Associated With Parvovirus B19 Infection: A Case Report

Human parvovirus B19 (HPV-B19) usually infects children. We report a case of an adult with HPV-B19 infection mimicking systemic lupus erythematosus (SLE). A previously healthy 46-year-old woman presented with an acute illness of cough, fever, chilling, polyarthritis, and skin rash. Laboratory findings showed pancytopenia, increased creatinine level, proteinuria and hypocomplementemia. Anti-double stranded DNA antibody (anti-dsDNA Ab) and antinuclear antibody were positive. Highly suspected of SLE based on clinical and laboratory findings, the patient was initially treated with corticosteroids. Meanwhile, the result of HPV-B19 polymerase chain reaction, which was done initially with other viral tests to exclude infection, turned out to be positive. Steroid was tapered, and pancytopenia, proteinuria, hypocomplementemia gradually improved. On the seventh day, anti-dsDNA Ab was found to be negatively converted. HPV-B19 infections are mostly self-limited and occur rarely in adults, but if a patient presents lupus-like syndrome with transient autoantibody positivity, lupus mimickers including HPV-B19 should be considered.

Lung cancer mimicking systemic lupus erythematosus: case-based review

The aim of this study was to analyze the clinical features of lupus-like lung adenocarcinoma, thus improving both the recognition of lupus mimickers and diagnosis accuracy. We collected three cases of lung adenocarcinoma in which the clinical characteristics and laboratory profiles imitated systemic lupus erythematosus (SLE) in our hospital, and also we had a literature review using search engine. There are few reports of lung adenocarcinoma for which the clinical and laboratory profiles meet the criteria for SLE diagnosis. Follow-up and pathological biopsy are beneficial for the differential diagnosis. Few lung adenocarcinoma cases resemble SLE. Gene pleiotropy and immune dysregulation might be contributing factors. Lung adenocarcinoma should be considered in the differential diagnosis of SLE. Follow-up and pathological biopsy should be improved to enable early detection of lung adenocarcinoma-associated lupus-like conditions.

Preclinical and early systemic lupus erythematosus

The challenge of early diagnosis and treatment is a timely issue in the management of systemic lupus erythematosus (SLE), as autoimmunity starts earlier than its clinical manifestations. Hence, growing efforts for stratification of patients according to the individual risk of developing specific clinical manifestations and/or predicting a better response to a given treatment have led to the proposal of several biomarkers, which require validation for use in clinical practice. In this viewpoint, we aim at distinguishing and discussing the features and the approach to asymptomatic immunological abnormalities potentially heralding the development of SLE, defined as preclinical lupus, and clinical manifestations consistent with SLE not yet fulfilling classification criteria, defined as early lupus. In case of preclinical SLE, careful surveillance using available screening tools is paramount, while patients with early lupus deserve an appropriate and timely diagnosis and, consequently, a proper treatment including hydroxychloroquine as the anchor drug.

Systemic Lupus Erythematosus in Primary Care: An Update and Practical Messages for the General Practitioner

Systemic Lupus Erythematosus (SLE) is a complex chronic autoimmune disease that manifests a wide range of organ involvement. Traditionally, the diagnosis and management of SLE is provided at secondary and tertiary centers to ensure prompt initiation of treatment, adequate control of flares and prevention of irreversible organ damage. Notwithstanding, the role of primary care in SLE is also emerging as there are still significant unmet needs such as the diagnostic delay at the community level and the high burden of therapy- and disease-related comorbidities. In the present review, we summarize practical messages for primary care physicians and general practitioners (GPs) concerning early diagnosis and proper referral of patients with SLE. In addition, we discuss the main comorbidities complicating the disease course and the recommended preventative measures, and we also provide an update on the role and current educational needs of GPs regarding the disease.

The Clinical Relevance of Anti-DFS70 Autoantibodies

Despite all the progress in the establishment of specific autoantibody assays, screening for antinuclear antibodies (ANA) by indirect immunofluorescence on HEp-2 cells for quality-oriented laboratory diagnosis of ANA associated rheumatic diseases (AARD) remains indispensable but is not without limitations. Recent data on the relevance of the dense fine speckled (DFS) pattern and anti-DFS70 antibodies disclosed novel possibilities to optimize the serological stepwise diagnostics of AARD. The DFS pattern on HEp-2 cells is well differentiated from the classic "homogeneous" ANA pattern associated with dsDNA antibodies. This is the most frequent pattern in high titer ANA-positive healthy persons. The most characteristic ANA specificity associated with DFS pattern is the anti-DFS70 antibody (synonym LEDGF antibody). The prevalence of anti-DFS70 antibodies in AARD patients is significantly lower compared with the prevalence in ANA-positive healthy persons. There is a negative association between anti-DFS70 antibodies and AARD, especially if no concomitant AARD-specific autoantibodies are found. Isolated anti-DFS70 antibodies are detectable in less than 1 % of AARD but are detectable in 2-22 % of healthy persons. In the presence of an isolated anti-DFS70 antibody, the posttest probability for AARD is reduced significantly. The significance of anti-DFS70 antibodies as a criterion that helps to exclude AARD is also confirmed by follow-up studies on anti-DFS70 antibodies of positive, healthy individuals, who did not develop any AARD during a 4 year observation period. Consequently, anti-DFS70 antibodies are valuable novel biomarkers for better interpretation of positive ANA in cases of negative AARD-associated autoantibodies and should be integrated in modified test algorithms to avoid unnecessary referrals and examinations of ANA-positive persons.

Infection and Lupus: Which Causes Which?

Infection is a leading cause of morbidity and mortality among patients with systemic lupus erythematous (SLE). Dysfunction of the innate and adaptive immune systems increases the risk of infection in patients with SLE. Infectious agents have also been theorized to play a role in the pathogenesis of SLE. This article summarizes our current knowledge of the infectious risk SLE patients face as a result of their underlying disease including abnormal phagocytes and T cells as well as the increased risk of infection associated with immunosuppressive agents used to treat disease. Pathogens thought to play a role in the pathogenesis of disease including EBV, CMV, human endogenous retroviruses (HERVs), and tuberculosis will also be reviewed, as well as the pathologic potential of microbial amyloids and the microbiome.

Autoimmunity in 2014

Our PubMed search for peer-reviewed articles published in the 2014 solar year retrieved a significantly higher number of hits compared to 2013 with a net 28 % increase. Importantly, full articles related to autoimmunity constitute approximately 5 % of immunology articles. We confirm that our understanding of autoimmunity is becoming a translational paradigm with pathogenetic elements rapidly followed by new treatment options. Furthermore, numerous clinical and pathogenetic elements and features are shared among autoimmune diseases, and this is well illustrated in the recent literature. More specifically, the past year witnessed critical revisions of our understanding and management of antiphospholipid syndrome with new exciting data on the pathogenicity of the serum anti-beta2 glycoprotein autoantibody, a better understanding of the current and new treatments for rheumatoid arthritis, and new position papers on important clinical questions such as vaccinations in patients with autoimmune disease, comorbidities, or new classification criteria. Furthermore, data confirming the important connections between innate immunity and autoimmunity via toll-like receptors or the critical role of T regulatory cells in tolerance breakdown and autoimmunity perpetuation were also reported. Lastly, genetic and epigenetic data were provided to confirm that the mosaic of autoimmunity warrants a susceptible individual background which may be geographically determined and contribute to the geoepidemiology of diseases. The 2014 literature in the autoimmunity world should be cumulatively regarded as part of an annus mirabilis in which, on a different level, the 2014 Annual Meeting of the American College of Rheumatology in Boston was attended by over 16,000 participants with over selected 3000 abstracts.

Pseudo-SLE by human immunodeficiency virus infection

A 61-year-old woman was admitted for long-lasting fever and recurrent opportunistic infections during the treatment of SLE. She had been diagnosed as SLE and type-IV nephritis based on a renal biopsy and serological findings. A colonoscopy and liver biopsy revealed disseminated Mycobacterium avium complex infection. Human immunodeficiency virus (HIV) infection status was then examined and found to be positive. From the clinical course, the first symptoms were inferred to have been those of HIV infection.

Infection-immunity liaison: pathogen-driven autoimmune-mimicry (PDAIM)

Autoimmunity causes pathological conditions resulting in autoimmune diseases (ADs). Although autoimmunity is a mystery, immunological dogma suggests that autoreactive cell reactivation (ACR) breaks self-tolerance and induces autoimmunity. Thus, ACR is a royal pathway for ADs. Cumulative evidence implicates environmental factors as secondary triggers of ADs in the genetically susceptible hosts. Infection is the most likely trigger. Although several mechanisms have been proposed to explain how infectious agents trigger ADs, ACR is assumed to be an essential pathway. Here, by showing some exemplary ADs, we propose two novel pathways, "molecular modification pathway" and "hyper-immune-inflammatory response pathway", which induce AD-like conditions directly by infectious agents without ACR. These AD-like conditions are actually not true "ADs" according to the current definition. Therefore, we define them as "pathogen-driven autoimmune-mimicry (PDAIM)". Confirming PDAIM will open perspectives in developing novel fundamental and non-immunosuppressive therapies for ADs. The idea should also provide novel insights into both the mechanisms of autoimmunity and the pathogenesis of ADs.

The role of imaging in the evaluation of joint involvement in 102 consecutive patients with systemic lupus erythematosus

OBJECTIVE

To assess the prevalence of joint involvement in consecutive patients with systemic lupus erythematosus (SLE) by means of clinical assessment, joint US and MRI and to evaluate the sensitivity and specificity of physician evaluation of joint involvement.

METHODS

At enrollment, patients underwent a complete physical examination including a 44-joint count, and hand deformities were scored. On the day of enrollment, each patient underwent a non-dominant hand-wrist ultrasound (US) examination and a non-dominant hand-wrist MRI study without contrast injection.

RESULTS

One hundred and two patients (F 95, M 7) were enrolled. By physician examination hand or wrist involvement was diagnosed in 23.5%. At least one pathological finding was revealed by US examination at wrist and/or hand joints in 55%. We found a low sensitivity (46.5%) with high specificity (93.2%) of the physician assessment for the evaluation of joint involvement. The MRI imaging showed at least one erosion in 47.3% patients at the hand and in 98.9% at the wrist; in healthy subjects erosions were found in 19.6% and 97.8% at the hand and wrist, respectively.

CONCLUSIONS

In conclusion, (i) physicians tend to underestimate the severity of joint involvement in SLE; (ii) US assessment shows a high prevalence of joint and tendon involvement; and (iii) the MRI evaluation shows a high prevalence of damage, suggesting that joint involvement in SLE could be more severe than expected.